Alliric I. Willis

Vascular smooth muscle cell migration: current research and clinical implications.

Atherosclerosis and intimal hyperplasia are major causes of morbidity and mortality. These processes develop secondary to endothelial injury due to multiple stimuli, including smoking, diabetes mellitus, hypertension, and hyperlipidemia. Once this injury occurs, an essential element in the development of both these processes is vascular smooth muscle cell (VSMC) migration. Understanding the mechanisms involved in VSMC migration and ultimately the development of strategies by which this process can be inhibited, has been a major focus of research. The authors present a review of the extracellular proteins (growth factors, extracellular matrix components, and cell surface receptors) and intracellular signaling pathways involved in VSMC migration, as well as potential therapeutic approaches to inhibit this process.

Prognostic Significance of Signet Ring Gastric Cancer

PURPOSE Studies in Asia have questioned the dictum that signet ring cell carcinoma (SRC) has a worse prognosis than other forms of gastric cancer. Our study determined differences in presentation and outcomes between SRC and gastric adenocarcinoma (AC) in the United States. PATIENTS AND METHODS The National Cancer Institute Surveillance, Epidemiology, and End Results database was reviewed for SRC and AC from 2004 to 2007. RESULTS We reviewed 10,246 cases of patients with gastric cancer, including 2,666 of SRC and 7,580 of AC. SRC presented in younger patients (61.9 v 68.7 years; P < .001) and less often in men (52.7% v 68.7%; P < .001). SRC patients were more frequently black (11.3% v 10.9%), Asian (16.4% v 13.2%), American Indian/Alaska Native (0.9% v 0.8%), or Hispanic (23.3% v 14.0%; P < .001). SRC was more likely to be stage T3-4 (45.8% v 33.3%), have lymph node spread (59.7% v 51.8%), and distant metastases (40.2% v 37.6%; P < .001). SRC was more likely to be found in the lower (30.7% v 24.2%) and middle stomach (30.6% v 20.7%; P < .001). Median survival was not different between the two (AC, 14.0 months v SRC, 13.0 months; P = .073). Multivariable analyses demonstrated SRC was not associated with mortality (hazard ratio [HR], 1.05; 95% CI, 0.96 to 1.11; P = .150). Mortality was associated with age (HR, 1.01; 95% CI, 1.01 to 1.02; P < .001), black race (HR, 1.10; 95% CI, 1.01 to 1.20; P = .026), and tumor grade. Variables associated with lower mortality risk included Asian race (HR, 0.83; 95% CI, 0.77 to 0.91; P < .001) and surgery (HR, 0.37; 95% CI, 0.34 to 0.39; P < .001). CONCLUSION In the United States, SRC significantly differs from AC in extent of disease at presentation. However, when adjusted for stage, SRC does not portend a worse prognosis.

Discordant lymphatic drainage patterns revealed by serial lymphoscintigraphy in cutaneous head and neck malignancies.

We analyzed the variability and accuracy of sentinel lymph node (SLN) identification by lymphoscintigraphy performed preoperatively and repeated on the day of operation in patients with melanoma or Merkel cell cancer.

Cyclic stretch induces the expression of vascular endothelial growth factor in vascular smooth muscle cells.

OBJECTIVE Accumulating evidence links the release of vascular endothelial growth factor (VEGF) by vascular smooth muscle cells (VSMC) to normal endothelial cell (EC) function, repair and maintenance. Using an in vitro model we investigate the role of cyclic stretch on both the release of VEGF by VSMC and the phosphorylation of a VEGF receptor on EC. METHODS Bovine VSMC and EC were exposed to 10% cyclic strain for 4 hours. VEGF mRNA steady-state levels of VSMC were analysed by northern blot hybridisation. The presence of secreted VEGF from VSMC was determined by assaying the migration of EC. VEGF receptor phosphorylation on stretched EC was assayed by immunoblotting. RESULTS The steady-state level of VEGF mRNA in stretched VSMC increased 3.3 (+/- 0.6) fold above that of unstretched VSMC (p < 0.005). Migration of EC was stimulated 8.3 (+/- 1.1) and 14.6 (+/- 1.3) fold by media from unstretched and stretched VSMC respectively, demonstrating a 1.8 fold increase due to stretch alone (p < 0.05). Cyclic stretch resulted in phosphorylation of the VEGF receptor KDR. CONCLUSION Exposure of VSMC to physiological levels of stretch induces a biologically significant increase in VEGF secretion and may provide an arterial stimulus for maintenance of steady state levels of VEGF essential for EC survival.

Thrombospondin-1 regulation of smooth muscle cell chemotaxis is extracellular signal-regulated protein kinases 1/2 dependent.

BACKGROUND Thrombospondin-1 (TSP-1), an extracellular matrix protein, induces vascular smooth muscle cell (VSMC) chemotaxis. We hypothesized that extracellular signal-regulated protein kinases 1/2 (ERK1/2), a pathway of the mitogen activated protein kinase (MAPK) family, is important in TSP-1-induced VSMC chemotaxis. METHODS A modified Boyden chamber was used to assess chemotaxis. First, a concentration curve was performed to determine the level for optimal TSP-1-induced chemotaxis. Then quiescent VSMCs were preincubated (30 minutes) in serum-free medium, dimethyl sulfoxide (the inhibitor vehicle), or PD98059 (10 mumol/L, an upstream inhibitor of ERK1/2). VSMCs (50,000 cells/well) with the appropriate preincubation were placed in the top chamber. The bottom chamber contained TSP-1 (20 micrograms/mL) or serum-free medium. Results were recorded as cells/5 fields (400x). Then quiescent VSMCs were exposed to TSP-1 (20 micrograms/mL) for 0, 1, 5, 10, 30, 120, or 300 minutes. Platelet-derived growth factor (10 ng/mL) was the positive control for ERK1/2 activation. Western blot analysis was performed for activated ERK1/2. All comparisons were made by a paired t test (n = 3). RESULTS TSP-1-induced chemotaxis peaks by a concentration of 20 micrograms/mL. PD98059 inhibited TSP-1-induced chemotaxis (P < .05). ERK1/2 was activated by TSP-1-stimulated VSMCs. CONCLUSIONS TSP-1-stimulated VSMCs activated ERK1/2. An ERK1/2 inhibitor abolished chemotaxis, suggesting the functional importance of MAPK in TSP-1-induced VSMC chemotaxis.

Thrombospondin-1 induces activation of focal adhesion kinase in vascular smooth muscle cells.

PURPOSE Vascular smooth muscle cell (VSMC) proliferation and migration are important events in the development of intimal hyperplasia. Thrombospondin-1 (TSP-1), an extracellular matrix protein present in intimal hyperplastic lesions, has been shown to stimulate VSMC proliferation and migration. We hypothesized that the focal adhesion plaque, specifically the focal adhesion kinase (FAK) protein, may be important in the signal transduction pathway for TSP-1-induced VSMC migration. METHODS Growth-arrested bovine aortic VSMCs were treated with TSP-1 (20 microg/mL) for set intervals (15, 30, and 120 minutes) and compared with VSMCs grown in serum-free medium (negative control) or in the presence of a known mitogen and chemotactic factor, platelet-derived growth factor (10 ng/mL; positive control). Crude cell lysates and anti-FAK immunoprecipitates were assayed for phosphotyrosine activity by means of antiphosphotyrosine immunoblotting. The blots were quantified by means of densitometric analysis. RESULTS TSP-1 increased tyrosine phosphorylation of three protein bands of molecular weights 68, 125 (consistent with FAK), and 180 kDa. Immunoprecipitation with FAK antibody, followed by antiphosphotyrosine immunoblotting, indicated that there was an increase in tyrosine phosphorylation of FAK at 15, 30, and 120 minutes in the TSP-1-treated groups (P <.05). CONCLUSION Tyrosine phosphorylation of FAK is induced by TSP-1 stimulated VSMCs. This suggests an outside-inside signaling pathway by which TSP-1 stimulates VSMC migration.

Examining rectal carcinoids in the era of screening colonoscopy: a surveillance, epidemiology, and end results analysis.

BACKGROUND: Little is known about the epidemiology of rectal carcinoids in the United States since the implementation of screening colonoscopy. OBJECTIVE: The goal of this study was to identify epidemiological differences between rectal and small intestinal carcinoids. DESIGN: This study was retrospective in design. SETTING: Surveillance, Epidemiology and End Results registry data from 1992 to 2008 were examined. PATIENTS: Patients with rectal carcinoids included those with carcinoid tumors of the rectum. Patients with small intestinal carcinoids included those with carcinoids in the duodenum, jejunum, or ileum. MAIN OUTCOME MEASURE: Epidemiological characteristics of rectal carcinoids were identified and compared with small intestinal carcinoids using multiple variable logistic regression. RESULTS: Patients with rectal carcinoids were more likely to be women (OR, 1.196 (95% CI, 1.090–1.311); p < 0.001). Rectal carcinoids were more common among all minorities, including Asians (OR, 10.063 (95% CI, 8.330–12.157); p < 0.001), blacks (OR, 1.994 (95% CI, 1.770–2.246); p < 0.001), and Hispanics (OR, 2.682 (95% CI, 2.291–3.141), p < 0.001). Patients in the 50- to 59-year age group (OR, 0.752 (95% CI, 0.599–0.944); p = 0.014) were more likely to be diagnosed with rectal carcinoids than those in the 60- to 69-year (OR, 0.481 (95% CI, 0.383–0.605); p < 0.001) and ≥70-year age groups (OR, 0.220 (95% CI, 0.175–0.277); p < 0.001). Rectal carcinoids were more likely to be diagnosed in the screening colonoscopy era among the 50- to 59-year age group (OR, 1.432 (95% CI, 1.082–1.895); p = 0.012). Since the implementation of screening colonoscopy in 2000, the proportion of patients diagnosed with rectal carcinoids has been greater than the proportion diagnosed with small intestinal carcinoids in every year except 2001, and the proportion of patients diagnosed with rectal carcinoids after 2000 has been greater than the proportion diagnosed with small intestinal carcinoids in 12 of 13 Surveillance, Epidemiology, and End Results registry reporting agencies. CONCLUSIONS: Rectal carcinoids and small intestinal carcinoids are epidemiologically distinct tumors with unique presentations. In the era of screening colonoscopy, rectal carcinoids are the more common tumor.

Gadd45a levels in human breast cancer are hormone receptor dependent

BackgroundGadd45a is a member of the Gadd45 family of genes that are known stress sensors. Gadd45a has been shown to serve as an effector in oncogenic stress in breast carcinogenesis in murine models. The present study was aimed at clarifying the expression of Gadd45a in human breast cancer and its correlation with clinicopathologic features.MethodsThe expression levels of Gadd45a in breast tissue samples of female breast surgery cases were examined by immunohistochemistry (IHC) using a Gadd45a antibody. Percent staining was determined and statistical analyses were applied to determine prognostic correlations.Results56 female breast surgery cases were studied: Normal (11), Luminal A (9), Luminal B (11), HER2+ (10), Triple Negative (15). There was a highly significant difference in percent Gadd45a staining between groups [Mean]: Normal 16.3%; Luminal A 65.3%; Luminal B 80.7%; HER2+ 40.5%; TN 32%, P < 0.001, ANOVA. Gadd45a IHC levels for Normal cases found 82% negative/low. Luminal A breast cancer cases were found to be 67% high. Luminal B breast cancers were 100% high. Her2+ cases were 50% negative/low. Triple Negative cases were 67% negative/low. This difference in distribution of Gadd45a levels across breast cancer receptor subtypes was significant, P = 0.0009.ConclusionsGadd45a levels are significantly associated with hormone receptor status in human breast cancer. Normal breast tissue displays low Gadd45a levels. High Gadd45a levels are associated with Luminal A and Luminal B subtypes. Absence of hormone receptors in Triple Negative subtype is associated with Negative/Low levels of Gadd45a. Further studies are indicated to elucidate the role of Gadd45a in breast cancer as a potential prognosticator or target for treatment.

Does payer status matter in predicting penetrating trauma outcomes

BACKGROUND Few data exist regarding payer status as a predictor of outcomes in penetrating trauma. This study determined whether insurance status impacts in-hospital complications and mortality in gunshot and stab wound patients at our inner-city, level I trauma center. METHODS Penetrating trauma admissions from 2005 to 2009 were reviewed for patient demographics, insurance, Injury Severity Score, complications, duration of stay, and mortality. RESULTS A total of 1,347 penetrating trauma patients were admitted with 652 (48.4%) uninsured. Although uninsured patients were more likely to be male (93.3% vs 89.8%, P = .030), there was no difference in age, ISS, or number of radiologic, operative, or interventional procedures. Uninsured patients had lesser intensive care unit (4.4 vs 3.3 days; P = .049) and total hospital length of stay (10.2 vs 8.3; P = .049). No uninsured patients were placed into a rehabilitation facility at the time of discharge (0.0% vs 1.6%, P < .001). There was no difference in frequency of pulmonary complications, thromboembolic complications, sepsis, urinary tract infection, or wound infections. On multivariate analysis, being uninsured was not an independent predictor of in-hospital complications (1.010, 95% confidence interval 0.703-1.450, P = .959) or mortality (odds ratio 0.905, 95% confidence interval 0.523-1.566, P = .722). CONCLUSION This is the first study to show that penetrating trauma patients who are uninsured have lesser duration of stay and decreased placement into a rehabilitation facility. Being uninsured added no additional risk of in-hospital complications or mortality.

Thrombospondin 1, Fibronectin, and Vitronectin are Differentially Dependent Upon RAS, ERK1/2, and p38 for Induction of Vascular Smooth Muscle Cell Chemotaxis

Background: Thrombospondin 1 (TSP-1), fibronectin (Fn), and vitronectin (Vn) promote vascular smooth muscle cell (VSMC) chemotaxis through a variety of second messenger systems, including Ras, ERK1/2, and p38. Hypothesis: Ras, ERK1/2, and p38 differentially affect TSP-1-, Fn-, and Vn-induced VSMC chemotaxis. Methods: Bovine VSMCs were transfected with Ras N17 or treated with the following inhibitors: a farnesyl protein transferase (FPT) inhibitor, PD098059 (ERK1/2 inhibitor), or SB202190 (p38 inhibitor). Thrombospondin 1, Fn, and Vn were used as chemoattractants. Results were analyzed by analysis of variance (ANOVA) with post hoc testing (P < .05). Results: Ras N17 transfection or FPT inhibitor treatment inhibited TSP-1-, Fn-, and Vn-induced chemotaxis. PD098059 or SB202190 resulted in more inhibition of VSMC migration to TSP-1 than to Fn or Vn. Conclusions: Ras appears equally relevant in the signal transduction pathways of TSP-1-, Fn-, and Vn-induced VSMC chemotaxis. Thrombospondin 1-induced migration is more dependent upon ERK1/2 and p38 than Fn- or Vn-included migration.